Inbred maize line 413A

ABSTRACT

An inbred maize line, designated 413A, having higher row number and smaller kernel width compared to Ia2132, and herbicide tolerance, the plants and seeds of inbred maize line 413A and descendants thereof, methods for producing a maize plant produced by crossing the inbred line 413A with itself or with another maize plant, and hybrid maize seeds and plants produced by crossing the inbred line 413A with another maize line or plant.

FIELD OF THE INVENTION

[0001] This invention is in the field of maize breeding, specificallyrelating to an inbred maize line designated 413A.

BACKGROUND OF THE INVENTION

[0002] The goal of plant breeding is to combine in a single variety orhybrid various desirable traits. For field crops, these traits mayinclude resistance to diseases and insects, tolerance to heat anddrought, reducing the time to crop maturity, greater yield, and betteragronomic quality. With mechanical harvesting of many crops, uniformityof plant characteristics such as germination and stand establishment,growth rate, maturity, and plant and ear height, is important.

[0003] Field crops are bred through techniques that take advantage ofthe plant's method of pollination. A plant is self-pollinated if pollenfrom one flower is transferred to the same or another flower of the sameplant. A plant is cross-pollinated if the pollen comes from a flower ona different plant. Plants that have been self-pollinated and selectedfor type for many generations become homozygous at almost all gene lociand produce a uniform population of true breeding progeny. A crossbetween two different homozygous lines produces a uniform population ofhybrid plants that may be heterozygous for many gene loci. A cross oftwo plants each heterozygous at a number of gene loci will produce apopulation of hybrid plants that differ genetically and will not beuniform.

[0004] Maize (Zea mays L.), often referred to as corn in the UnitedStates, can be bred by both self-pollination and cross-pollinationtechniques. Maize has separate male and female flowers on the sameplant, located on the tassel and the ear, respectively. Naturalpollination occurs in maize when wind blows pollen from the tassels tothe silks that protrude from the tops of the ears.

[0005] A reliable method of controlling male fertility in plants offersthe opportunity for improved plant breeding. This is especially true fordevelopment of maize hybrids, which relies upon some sort of malesterility system. There are several options for controlling malefertility available to breeders, such as: manual or mechanicalemasculation (or detasseling), cytoplasmic male sterility, genetic malesterility, gametocides and the like.

[0006] Hybrid maize seed is typically produced by a male sterilitysystem incorporating manual or mechanical detasseling. Alternate stripsof two maize inbreds are planted in a field, and the pollen-bearingtassels are removed from one of the inbreds (female). Providing thatthere is sufficient isolation from sources of foreign maize pollen, theears of the detasseled inbred will be fertilized only from the otherinbred (male) and the resulting seed is therefore hybrid and will formhybrid plants.

[0007] The laborious, and occasionally unreliable, detasseling processcan be avoided by using cytoplasmic male-sterile (CMS) inbreds. Plantsof a CMS inbred are male sterile as a result of factors resulting fromthe cytoplasmic, as opposed to the nuclear, genome. Thus, thischaracteristic is inherited exclusively through the female parent inmaize plants, since only the female provides cytoplasm to the fertilizedseed. CMS plants are fertilized with pollen from another inbred that isnot male-sterile. Pollen from the second inbred may or may notcontribute genes that make the hybrid plants male-fertile. Seed fromdetasseled fertile maize and CMS produced seed of the same hybrid can beblended to insure that adequate pollen loads are available forfertilization when the hybrid plants are grown.

[0008] There are several methods of conferring genetic male sterilityavailable, such as multiple mutant genes at separate locations withinthe genome that confer male sterility, as disclosed in U.S. Pat. Nos.4,654,465 and 4,727,219 and chromosomal translocations as described inU.S. Pat. Nos. 3,861,709 and 3,710,511, the disclosures of which arespecifically incorporated herein by reference. There are many othermethods of conferring genetic male sterility in the art, each with itsown benefits and drawbacks. These methods use a variety of approachessuch as delivering into the plant a gene encoding a cytotoxic substanceassociated with a male tissue specific promoter or an antisense systemin which a gene critical to fertility is identified and an antisense tothat gene is inserted in the plant (EPO 89/3010153.8 and WO 90/08828).

[0009] Another system useful in controlling male sterility makes use ofgametocides. Gametocides are not a genetic system, but rather a topicalapplication of chemicals. These chemicals affect cells that are criticalto male fertility. The application of these chemicals affects fertilityin the plants only for the growing season in which the gametocide isapplied (see Carlson, Glenn R., U.S. Pat. No. 4,936,904, which isincorporated herein by reference). Application of the gametocide, timingof the application and genotype specificity often limit the usefulnessof the approach.

[0010] The use of male sterile inbreds is but one factor in theproduction of maize hybrids. The development of maize hybrids requires,in general, the development of homozygous inbred lines, the crossing ofthese lines, and the evaluation of the crosses. Pedigree breeding andrecurrent selection breeding methods are used to develop inbred linesfrom breeding populations. Breeding programs combine the geneticbackgrounds from two or more inbred lines or various other germplasmsources into breeding pools from which new inbred lines are developed byselfing and selection of desired phenotypes. The new inbreds are crossedwith other inbred lines and the hybrids from these crosses are evaluatedto determine which of those have commercial potential. Plant breedingand hybrid development are expensive and time-consuming processes.

[0011] Pedigree breeding starts with the crossing of two genotypes, eachof which may have one or more desirable characteristics that is lackingin the other or which complements the other. If the two original parentsdo not provide all the desired characteristics, other sources can beincluded in the breeding population. In the pedigree method, superiorplants are selfed and selected in successive generations. In thesucceeding generations the heterozygous condition gives way tohomogeneous lines as a result of self-pollination and selection.Typically in the pedigree method of breeding five or more generations ofselfing and selection is practiced: F1 to F2; F3 to F4; F4 to F5, etc.

[0012] Recurrent selection breeding can be used to improve populationsof either self or cross-pollinating crops. Recurrent selection can beused to transfer a specific desirable trait from one inbred or source toan inbred that lacks the trait. This can be accomplished, for example,by first a superior inbred (recurrent parent) to a donor inbred(non-recurrent parent), that carries the appropriate gene(s) for thetrait in question. The progeny of this cross is then mated back to thesuperior recurrent parent followed by selection in the resultant progenyfor the desired trait to be transferred from the non-recurrent parent.After five or more backcross generations with selection for the desiredtrait, the progeny will be homozygous for loci controlling thecharacteristic being transferred, but will be like the superior parentfor essentially all other genes. The last backcross generation is, thenselfed to give pure breeding progeny for the gene(s) being transferred.A hybrid developed from inbreds containing the transferred gene(s) isessentially the same as a hybrid developed form the same inbreds withoutthe transferred genes. As the varieties developed using recurrentselection breeding contain almost all of the characteristics of therecurrent parent, selecting a superior recurrent parent is desirable.

[0013] A single cross maize hybrid results from the cross of two inbredlines, each of which has a genotype that complements the genotype of theother. The hybrid progeny of the first generation is designated F1. Inthe development of commercial hybrids only the F1 hybrid plants aresought. Preferred F1 hybrids are more vigorous than their inbredparents. This hybrid vigor, or heterosis, can be manifested in manypolygenic traits, including increased vegetative growth and increasedyield.

[0014] The development of a maize hybrid involves three steps: (1) theselection of plants from various germplasm pools for initial breedingcrosses; (2) the selfing of the selected plants from the breedingcrosses for several generations to produce a series of inbred lines,which, although different from each other, breed true and are highlyuniform; and (3) crossing the selected inbred lines with differentinbred lines to produce the hybrid progeny (F1). During the inbreedingprocess in maize, the vigor of the lines decreases. Vigor is restoredwhen two different inbred lines are crossed to produce the hybridprogeny (F1). An important consequence of the homozygosity andhomogeneity of the inbred lines is that the hybrid between a definedpair of inbreds will always be the same. Once the inbreds that give asuperior hybrid have been identified, the hybrid seed can be reproducedindefinitely as long as the homogeneity of the inbred parents ismaintained.

[0015] A single cross hybrid is produced when two inbred lines arecrossed to produce the F1 progeny. A double cross hybrid is producedfrom four inbred lines crossed in pairs (A×B and C×D) and then the twoF1 hybrids are crossed again (A×B)×(C×D). Much of the hybrid vigorexhibited by F1 hybrids is lost in the next generation (F2).Consequently, seed from hybrids is not used for planting stock.

[0016] Hybrid seed production requires elimination or inactivation ofpollen produced by the female parent. Incomplete removal or inactivationof the pollen provides the potential for self-pollination. Thisinadvertently self-pollinated seed may be unintentionally harvested andpackaged with hybrid seed. Once the seed is planted, it is possible toidentify and select these self-pollinated plants. These self-pollinatedplants will be genetically equivalent to the female inbred line used toproduce the hybrid. Typically these self-pollinated plants can beidentified and selected due to their decreased vigor. Female selfs areidentified by their less vigorous appearance for vegetative and/orreproductive characteristics, including shorter plant height, small earsize, ear and kernel shape, cob color, or other characteristics.

[0017] Identification of these self-pollinated lines can also beaccomplished through molecular marker analyses. See, “The Identificationof Female Selfs in Hybrid Maize: A Comparison Using Electrophoresis andMorphology”, Smith, J. S. C. and Wych, R. D., Seed Science andTechnology 14, pp. 1-8 (1995), the disclosure of which is expresslyincorporated herein by reference. Through these technologies, thehomozygosity of the self-pollinated line can be verified by analyzingallelic composition at various loci along the genome. Those methodsallow for rapid identification of the invention disclosed herein. Seealso, “Identification of Atypical Plants in Hybrid Maize Seed byPostcontrol and Electrophoresis” Sarca, V. et al., Probleme de GeneticaTeoritca si Aplicata Vol. 20 (1) p. 29-42.

[0018] As is readily apparent to one skilled in the art, the foregoingdescribes only two of the various ways by which the inbred can beobtained by those looking to use the germplasm. Other means areavailable, and the above examples are illustrative only.

[0019] Maize is an important and valuable field crop. Thus, a continuinggoal of plant breeders is to develop high-yielding maize hybrids thatare agronomically sound based on stable inbred lines. The reasons forthis goal are obvious: to maximize the amount of grain produced with theinputs used and minimize susceptibility of the crop to pests andenvironmental stresses. To accomplish this goal, the maize breeder mustselect and develop superior inbred parental lines for producing hybrids.This requires identification and selection of genetically uniqueindividuals that occur in a segregating population. The segregatingpopulation is the result of a combination of crossover events plus theindependent assortment of specific combinations of alleles at many geneloci that results in specific genotypes. The probability of selectingany one individual with a specific genotype from a breeding cross isinfinitesimal due to the large number of segregating genes and theunlimited recombinations of these genes, some of which may be closelylinked. However, the genetic variation among individual progeny of abreeding cross allows for the identification of rare and valuable newgenotypes. These new genotypes are neither predictable nor incrementalin value, but rather the result of manifested genetic variation combinedwith selection methods, environments and the actions of the breeder.Thus, even if the entire genotypes of the parents of the breeding crosswere characterized and a desired genotype known, only a few, if any,individuals having the desired genotype may be found in a largesegregating F2 population. Typically, however, neither the genotypes ofthe breeding cross parents nor the desired genotype to be selected isknown in any detail. In addition, it is not known how the desiredgenotype would react with the environment. This genotype by environmentinteraction is an important, yet unpredictable, factor in plantbreeding. A breeder of ordinary skill in the art cannot predict thegenotype, how that genotype will interact with various climaticconditions or the resulting phenotypes of the developing lines, exceptperhaps in a very broad and general fashion. A breeder of ordinary skillin the art would also be unable to recreate the same line twice from thevery same original parents, as the breeder is unable to direct how thegenomes combine or how they will interact with the environmentalconditions. This unpredictability results in the expenditure of largeamounts of research resources in the development of a superior new maizeinbred line.

SUMMARY OF THE INVENTION

[0020] According to the invention, there is provided a novel inbredmaize line, designated 413A having higher row number and smaller kernelwidth compared to Ia2132, and herbicide tolerance. This invention thusrelates to the seeds of inbred maize line 413A, to the plants of inbredmaize line 413A, and to methods for producing a maize plant by crossingthe inbred line 413A with itself or another maize line. This inventionfurther relates to hybrid maize seeds and plants produced by crossingthe inbred line 413A with another maize line.

[0021] The invention is also directed to inbred maize line 413A intowhich one or more specific, single gene traits, for example transgenes,have been introgressed from another maize line. Preferably, theresulting line has essentially all of the morphological andphysiological characteristics of inbred maize line of 413A, in additionto the one or more specific, single gene traits introgressed into theinbred, preferably the resulting line has all of the morphological andphysiological characteristics of inbred maize line of 413A, in additionto the one or more specific, single gene traits introgressed into theinbred. The invention also relates to seeds of an inbred maize line 413Ainto which one or more specific, single gene traits have beenintrogressed and to plants of an inbred maize line 413A into which oneor more specific, single gene traits have been introgressed. Theinvention further relates to methods for producing a maize plant bycrossing plants of an inbred maize line 413A into which one or morespecific, single gene traits have been introgressed with themselves orwith another maize line. The invention also further relates to hybridmaize seeds and plants produced by crossing plants of an inbred maizeline 413A into which one or more specific, single gene traits have beenintrogressed with another maize line. The invention is also directed toa method of producing inbreds comprising planting a collection of hybridseed, growing plants from the collection, identifying inbreds among thehybrid plants, selecting the inbred plants and controlling theirpollination to preserve their homozygosity.

DETAILED DESCRIPTION OF THE INVENTION

[0022] Inbred maize lines are typically developed for use in theproduction of hybrid maize lines. Inbred maize lines need to be highlyhomogeneous, homozygous and reproducible to be useful as parents ofcommercial hybrids. There are many analytical methods available todetermine the homozygotic and phenotypic stability of these inbredlines.

[0023] The oldest and most traditional method of analysis is theobservation of phenotypic traits. The data is usually collected in fieldexperiments over the life of the maize plants to be examined. Phenotypiccharacteristics most often observed are for traits associated with plantmorphology, ear and kernel morphology, insect and disease resistance,maturity, and yield.

[0024] In addition to phenotypic observations, the genotype of a plantcan also be examined. There are many laboratory-based techniquesavailable for the analysis, comparison and characterization of plantgenotype; among these are Isozyme Electrophoresis, Restriction FragmentLength Polymorphisms (RFLPs), Randomly Amplified Polymorphic DNAs(RAPDs), Arbitrarily Primed Polymerase Chain Reaction (AP-PCR), DNAAmplification Fingerprinting (DAF), Sequence Characterized AmplifiedRegions (SCARs), Amplified Fragment Length Polymorphisms (AFLPs), andSimple Sequence Repeats (SSRs) which are also referred to asMicrosatellites.

[0025] Some of the most widely used of these laboratory techniques areIsozyme Electrophoresis and RFLPs as discussed in Lee, M., “Inbred Linesof Maize and Their Molecular Markers,” The Maize Handbook,(Springer-Verlag, New York, Inc. 1994, at 423-432). IsozymeElectrophoresis is a useful tool in determining genetic composition,although it has relatively low number of available markers and the lownumber of allelic variants among maize inbreds. RFLPs have the advantageof revealing an exceptionally high degree of allelic variation in maizeand the number of available markers is almost limitless. Maize RFLPlinkage maps have been rapidly constructed and widely implemented ingenetic studies. One such study is described in Boppenmaier, et al.,“Comparisons among strains of inbreds for RFLPs”, Maize GeneticsCooperative Newsletter, 65:1991, pg. 90. This study used 101 RFLPmarkers to analyze the patterns of 2 to 3 different deposits each offive different inbred lines. The inbred lines had been selfed from 9 to12 times before being adopted into 2 to 3 different breeding programs.It was results from these 2 to 3 different breeding programs thatsupplied the different deposits for analysis. These five lines weremaintained in the separate breeding programs by selfing or sibbing androgueing off-type plants for an additional one to eight generations.After the RFLP analysis was completed, it was determined the five linesshowed 0-2% residual heterozygosity. Although this was a relativelysmall study, it can be seen using RFLPs that the lines had been highlyhomozygous prior to the separate strain maintenance.

[0026] The production of hybrid maize lines typically comprises plantingin pollinating proximity seeds of, for example, inbred maize line 413Aand of a different inbred parent maize plant, cultivating the seeds ofinbred maize line 413A and of said different inbred parent maize plantinto plants that bear flowers, emasculating the male flowers of inbredmaize line 413A or the male flowers of said different inbred parentmaize plant to produce an emasculated maize plant, allowingcross-pollination to occur between inbred maize line 413A and saiddifferent inbred parent maize plant and harvesting seeds produced onsaid emasculated maize plant. The harvested seed are grown to producehybrid maize plants.

[0027] Inbred maize line 413A can be crossed to inbred maize lines ofvarious heterotic group (see e.g. Hallauer et al. (1988) in Corn andCorn Improvement, Sprague et al, eds, chapter 8, pages 463-564) for theproduction of hybrid maize lines. TABLE I VARIETY DESCRIPTIONINFORMATION Inbred maize line 413A is compared to inbred Ia2132 413AIa2132 PLANT Mean Std Dev Mean Std Dev LSD .05 Sig Y/N Plant height (cm)200.6 13.5 168.4 14.1 4.93 Y Ear height (cm) 76.2 9.8 40.0 17.0 3.63 YInternode length (cm) 14.0 2.0 14.6 2.2 0.78 N Number of tillers 1.7 1.02.0 0.6 0.32 Y Ears per stalk 1.1 0.2 1.5 0.8 0.24 Y LEAF Mean Std DevMean Std Dev LSD 0.5 Sig Y/N Width of ear node leaf 5.4 0.5 5.9 1.3 0.41Y (cm) Length of ear node leaf 82.8 0.5 60.9 8.7 2.99 Y (cm) Number ofleaves above 4.6 0.5 5.3 0.7 0.23 Y Leaf angle (degrees from 3.2 5.465.8 10.3 2.89 Y top of stalk) TASSEL Mean Std Dev Mean Std Dev LSD 0.5Sig Y/N Number of Primary 11.9 3.0 18.1 2.6 1.19 Y Lateral BranchesBranch Angle (degrees 75.4 11.3 35.8 4.4 3.67 Y from central spike)Tassel length (cm) 46.0 3.6 33.6 3.9 1.47 Y EAR Mean Std Dev Mean StdDev LSD 0.5 Sig Y/N Ear length (cm) 11.7 1.0 11.4 1.7 0.53 N Eardiameter (cm) 38.1 3.0 36.3 3.3 1.28 Y Row number 23.2 2.1 12.7 1.1 0.74Y Kernel length (mm) 11.6 0.9 10.7 1.4 0.43 Y Kernel width (mm) 6.5 0.68.3 0.9 0.35 Y Kernel thickness (mm) 3.0 0.2 3.4 0.8 0.25 N Percentageof round 3.9 3.2 35.8 11.9 3.81 Y kernels Weight of 100 kernels 11.1 2.119.5 2.4 1.02 Y (grams) Cob diameter (mm) 13.1 1.3 12.4 1.1 0.5 YDescriptive Ratings 413A Ia2132 (According to the PVP form) Leaf sheathpubescence 4.0 2.0 Marginal waves 6.0 5.0 Longitudinal creases 3.0 8.0Pollen shed 3 3 Kernel rows 1 Row alignment 2 2 Ear taper 2 2 Aleuronecolor pattern 1 1 Endosperm type 1 (su) 1 (su) Anthocyanin of brace 1 1roots MATURITY Days Heat Units Days Heat Units Emergence to 50% of 74 67plants in silk Emergence to 50% of 67 64 plants in pollen 50% silk tooptimum 95 88 edible quality COLOR PVP Code Munsell PVP Code MunsellLeaf 03 7.5gy4/4 03 7.5gy4/5 Anther 14 2.5r5/8 14 2.5r4/4 Glume 142.5r5/8 14 5r4/6 Silk 01 2.5gy8/6 14 5r5/6 Fresh husk 02 5gy6/6 025gy7/8

[0028] In interpreting the foregoing color designations, reference maybe made to the Munsell Glossy Book of Color, a standard color reference.Color codes: 1. light green, 2. medium green, 3. dark green, 4. verydark green, 5. green-yellow, 6. pale yellow, 7. yellow, 8.yellow-orange, 9. salmon, 10. pink-orange, 11. pink 12. light red, 13.cherry red, 14. red, 15. red and white, 16. pale purple, 17. purple, 18.colorless, 19. white, 20, white capped, 21. buff, 22. tan, 23. brown,24. bronze, 25. variegated, 26. other.

[0029] 413A differs from 1a2132 for several different traits. Thesetraits are:

[0030] The Plant Height of 413A is 201 cm while the plant height ofIa2132 is 168 cm.

[0031] The Length of Ear Node Leaf of 413A is 83 cm while the length ofear node leaf of Ia2132 is 61 cm.

[0032] The Leaf Angle of 413A is 3 degrees while the leaf angle ofIa2132 is 66 degrees. 15 The Longitudinal Creases on 413A is rated a 3and is significantly different than Ia2132, which is rated a 8.

[0033] The 413A tassel has fewer branches than the Ia2132 tassel. 413Ahas 12 Primary Tassel Branches and Ia2132 has 18. The Tassel BranchAngle of 413A is 75 degrees while the tassel branch angle for Ia2132 is36 degrees.

[0034] The ear of 413A is also different than the Ia2132 ear. The EarHeight of 413A is 76 cm while the ear height of Ia2132 is 40 cm. 413Aear has 4 Percent Round Kernels as compared to 36% on Ia2132. TABLE IIHybrid GH-5704 has inbred 413A and 363B as parents. Hybrids GH-5703 isused for comparison. GH-5704 is a Poast herbicide resistant version ofGH-5703 with the herbicide resistance coming From 413A. Mid Silk Ear Rownumber Husk Tip Trial ID Location Year Date Length ave. (in) ave. length(cm) fill (cm) Hybrid: GH-5704 T02NMP Nampa ID 2002 64 8 19.7 1 0.5T02MN1 Stanton MN 2002 72 7.4 20.7 0.5 1 T02TCF Othello WA 2002 na 8.2na 2 1 T02SMP Pasco, WA 2002 na 8 na 3 0.5 T02WILL Salem, OR 2002 na 7.6na 4 0 T01NMP Nampa ID 2001 63 8.1 22 0.5 0 T01MN1 Stanton MN 2001 817.8 21 0.5 3 Average: 70.0 7.9 20.9 1.6 0.9 Hybrid: GH-5703 T02NMP NampaID 2002 64 8.1 22 0.5 0.5 T02MN1 Stanton MN 2002 72 7.8 21 1 2 T02TCFOthello WA 2002 na 8 na 2 1 T02SMP Pasco, WA 2002 na 7.5 na 3 0.5T02WILL Salem, OR 2002 na 7.6 na 4 0 T01NMP Nampa ID 2001 64 8 19.3 1 1T01MN1 Stanton MN 2001 78 8 18.7 0 2.5 Average: 69.5 7.9 20.3 1.6 1.1

[0035] Mid silk date is the number of days from planting to 50% plantswith ear silk. Husk length is centimeters of husk past ear tip. Tip fillis centimeters of blank tip below tip of ear. Common rust is a scale of0-9 with 0 equals none and 9 equals most severe.

[0036] The invention also encompasses plants of inbred maize line 413Aand parts thereof further comprising one or more specific, single genetraits which have been introgressed into inbred maize line 413A fromanother maize line. Preferably, one or more new traits are transferredto inbred maize line 413A, or, alternatively, one or more traits ofinbred maize line 413A are altered or substituted. The transfer (orintrogression) of the trait(s) into inbred maize line 413A is forexample achieved by recurrent selection breeding, for example bybackcrossing. In this case, inbred maize line 413A (the recurrentparent) is first crossed to a donor inbred (the non-recurrent parent)that carries the appropriate gene(s) for the trait(s) in question. Theprogeny of this cross is then mated back to the recurrent parentfollowed by selection in the resultant progeny for the desired trait(s)to be transferred from the non-recurrent parent. After three, preferablyfour, more preferably five or more generations of backcrosses with therecurrent parent with selection for the desired trait(s), the progenywill be heterozygous for loci controlling the trait(s) beingtransferred, but will be like the recurrent parent for most or almostall other genes (see, for example, Poehlman & Sleper (1995) BreedingField Crops, 4th Ed., 172-175; Fehr (1987) Principles of CultivarDevelopment, Vol. 1: Theory and Technique, 360376).

[0037] The laboratory-based techniques described above, in particularRFLP and SSR, are routinely used in such backcrosses to identify theprogenies having the highest degree of genetic identity with therecurrent parent. This permits to accelerate the production of inbredmaize lines having at least 90%, preferably at least 95%, morepreferably at least 99% genetic identity with the recurrent parent, yetmore preferably genetically identical to the recurrent parent, andfurther comprising the trait(s) introgressed from the donor patent. Suchdetermination of genetic identity is based on molecular markers used inthe laboratory-based techniques described above. Such molecular markersare for example those known in the art and described in Boppenmaier, etal., “Comparisons among strains of inbreds for RFLPs”, Maize GeneticsCooperative Newsletter (1991) 65, pg. 90, or those available from theUniversity of Missouri database and the Brookhaven laboratory database.The last backcross generation is then selfed to give pure breedingprogeny for the gene(s) being transferred. The resulting plants haveessentially all of the morphological and physiological characteristicsof inbred maize line 413A, in addition to the single gene trait(s)transferred to the inbred. The exact backcrossing protocol will dependon the trait being altered to determine an appropriate testing protocol.Although backcrossing methods are simplified when the trait beingtransferred is a dominant allele, a recessive allele may also betransferred. In this instance it may be necessary to introduce a test ofthe progeny to determine if the desired trait has been successfullytransferred.

[0038] Many traits have been identified that are not regularly selectedfor in the development of a new inbred but that can be improved bybackcrossing techniques or genetic transformation. Examples of traitstransferred to inbred maize line 413A include, but are not limited to,waxy starch, herbicide tolerance, resistance for bacterial, fungal, orviral disease, insect resistance, enhanced nutritional quality, improvedperformance in an industrial process, altered reproductive capability,such as male sterility or male fertility, yield stability and yieldenhancement. Other traits transferred to inbred maize line 413A are forthe production of commercially valuable enzymes or metabolites in plantsof inbred maize line 413A.

[0039] Traits transferred to maize inbred line 413A are naturallyoccurring maize traits, which are preferably introgressed into inbredmaize line 413A by breeding methods such as backcrossing, or areheterologous transgenes, which are preferably first introduced into amaize line by genetic transformation using genetic engineering andtransformation techniques well known in the art, and then introgressedinto inbred line 413A. Alternatively a heterologous trait is directlyintroduced into inbred maize line 413A by genetic transformation.Heterologous, as used herein, means of different natural origin orrepresents a non-natural state. For example, if a host cell istransformed with a nucleotide sequence derived from another organism,particularly from another species, that nucleotide sequence isheterologous with respect to that host cell and also with respect todescendants of the host cell which carry that gene. Similarly,heterologous refers to a nucleotide sequence derived from and insertedinto the same natural, original cell type, but which is present in anon-natural state, e.g. a different copy number, or under the control ofdifferent regulatory sequences. A transforming nucleotide sequence maycomprise a heterologous coding sequence, or heterologous regulatorysequences. Alternatively, the transforming nucleotide sequence may becompletely heterologous or may comprise any possible combination ofheterologous and endogenous nucleic acid sequences.

[0040] A transgene introgressed into maize inbred line 413A typicallycomprises a nucleotide sequence whose expression is responsible orcontributes to the trait under the control of a promoter appropriate forthe expression of the nucleotide sequence at the desired time in thedesired tissue or part of the plant. Constitutive or inducible promotersare used. The transgene may also comprise other regulatory elements suchas for example translation enhancers or termination signals. In apreferred embodiment, the nucleotide sequence is the coding sequence ofa gene and is transcribed and translated into a protein. In anotherpreferred embodiment, the nucleotide sequence encodes an antisense RNA,a sense RNA that is not translated or only partially translated, at-RNA, a r-RNA or a sn-RNA.

[0041] Where more than one trait are introgressed into inbred maize line413A, it is preferred that the specific genes are all located at thesame genomic locus in the donor, non-recurrent parent, preferably, inthe case of transgenes, as part of a single DNA construct integratedinto the donor's genome. Alternatively, if the genes are located at Isdifferent genomic loci in the donor, non-recurrent parent, backcrossingallows to recover all of the morphological and physiologicalcharacteristics of inbred maize line 413A in addition to the multiplegenes in the resulting maize inbred line.

[0042] The genes responsible for a specific, single gene trait aregenerally inherited through the nucleus. Known exceptions are, e.g. thegenes for male sterility, some of which are inherited cytoplasmically,but still act as single gene traits. In a preferred embodiment, aheterologous transgene to be transferred to maize inbred line 413A isintegrated into the nuclear genome of the donor, non-recurrent parent.In another preferred embodiment, a heterologous transgene to betransferred to into maize inbred line 413A is integrated into theplastid genome of the donor, non-recurrent parent. In a preferredembodiment, a plastid transgene comprises one gene transcribed from asingle promoter or two or more genes transcribed from a single promoter.

[0043] In a preferred embodiment, a transgene whose expression resultsor contributes to a desired trait to be transferred to maize inbred line413A comprises a virus resistance trait such as, for example, a MDMVstrain B coat protein gene whose expression confers resistance to mixedinfections of maize dwarf mosaic virus and maize chlorotic mottle virusin transgenic maize plants (Murry et al. Biotechnology (1993)11:1559-64). In another preferred embodiment, a transgene comprises agene encoding an insecticidal protein, such as, for example, a crystalprotein of Bacillus thuringiensis or a vegetative insecticidal proteinfrom Bacillus cereus, such as VIP3 (see for example Estruch et al. NatBiotechnol (1997) 15:137-41). In a preferred embodiment, an insecticidalgene introduced into maize inbred line 413A is a Cry1Ab gene or aportion thereof, for example introgressed into maize inbred line 413Afrom a maize line comprising a Bt-11 event as described in U.S. Pat. No.6,114,608, which is incorporated herein by reference, or from a maizeline comprising a 176 event as described in Koziel et al. (1993)Biotechnology 11: 194-200. In yet another preferred embodiment, atransgene introgressed into maize inbred line 413A comprises a herbicidetolerance gene. For example, expression of an altered acetohydroxyacidsynthase (AHAS) enzyme confers upon plants tolerance to variousimidazolinone or sulfonamide herbicides (U.S. Pat. No. 4,761,373). Inanother preferred embodiment, a non-transgenic trait conferringtolerance to imidazolinones is introgressed into maize inbred line 413A(e.g a “IT” or “IR” trait). U.S. Pat. No. 4,975,374, incorporated hereinby reference, relates to plant cells and plants containing a geneencoding a mutant glutamine synthetase (GS) resistant to inhibition byherbicides that are known to inhibit GS, e.g. phosphinothricin andmethionine sulfoximine. Also, expression of a Streptomyces bar geneencoding a phosphinothricin acetyl transferase in maize plants resultsin tolerance to the herbicide phosphinothricin or glufosinate (U.S. Pat.No. 5,489,520). U.S. Pat. No. 5,013,659, which is incorporated herein byreference, is directed to plants that express a mutant acetolactatesynthase (ALS) that renders the plants resistant to inhibition bysulfonylurea herbicides. U.S. Pat. No. 5,162,602 discloses plantstolerant to inhibition by cyclohexanedione and aryloxyphenoxypropanoicacid herbicides. The tolerance is conferred by an altered acetylcoenzyme A carboxylase(ACCase). U.S. Pat. No. 5,554,798 disclosestransgenic glyphosate tolerant maize plants, which tolerance isconferred by an altered 5-enolpyruvyl-3-phosphoshikimate (EPSP) synthasegene. U.S. Pat. No. 5,804,425 discloses transgenic glyphosate tolerantmaize plants, which tolerance is conferred by an EPSP synthase genederived from Agrobacterium tumefaciens CP-4 strain. Also, tolerance to aprotoporphyrinogen oxidase inhibitor is achieved by expression of atolerant protoporphyrinogen oxidase enzyme in plants (U.S. Pat. No.5,767,373). Another trait transferred to inbred maize line 413A conferstolerance to an inhibitor of the enzyme hydroxyphenylpyruvatedioxygenase (HPPD) and transgenes conferring such trait are, forexample, described in WO 9638567, WO 9802562, WO 9923886, WO 9925842, WO9749816, WO 9804685 and WO 9904021. All issued patents referred toherein are, in their entirety, expressly incorporated herein byreference.

[0044] In a preferred embodiment, a transgene transferred to maizeinbred line 413A comprises a gene conferring tolerance to a herbicideand at least another nucleotide sequence encoding another trait, such asfor example, an insecticidal protein. Such combination of single genetraits is for example a Cry1Ab gene and a bar gene.

[0045] Specific transgenic events introgressed into maize inbred line413A can be obtained through the list of Petitions of NonregulatedStatus granted by APHIS as of 10-12-2000. For example, introgressed fromglyphosate tolerant event GA21 (9709901p), glyphosatetolerant/Lepidopteran insect resistant event MON 802 (9631701p),Lepidopteran insect resistant event DBT418 (9629101p), male sterileevent MS3 (9522801p), Lepidopteran insect resistant event Bt11(9519501p), phosphinothricin tolerant event B16 (9514501p), Lepidopteraninsect resistant event MON 80100 (9509301p), phosphinothricin tolerantevents T14, T25 (9435701p), Lepidopteran insect resistant event 176(9431901p).

[0046] The introgression of a Bt11 event into a maize line, such asmaize inbred line 413A, by backcrossing is exemplified in U.S. Pat. No.6,114,608, and the present invention is directed to methods ofintrogressing a Bt11 event into maize inbred line 413A using for examplethe markers described in U.S. Pat. No. 6,114,608 and to resulting maizelines.

[0047] Direct selection may be applied where the trait acts as adominant trait. An example of a dominant trait is herbicide tolerance.For this selection process, the progeny of the initial cross are sprayedwith the herbicide prior to the backcrossing. The spraying eliminatesany plant which does not have the desired herbicide tolerancecharacteristic, and only those plants that have the herbicide tolerancegene are used in the subsequent backcross. This process is then repeatedfor the additional backcross generations.

[0048] This invention also is directed to methods for producing a maizeplant by crossing a first parent maize plant with a second parent maizeplant wherein either the first or second parent maize plant is a maizeplant of inbred line 413A or a maize plant of inbred line 413A furthercomprising one or more single gene traits. Further, both first andsecond parent maize plants can come from the inbred maize line 413A oran inbred maize plant of 413A further comprising one or more single genetraits. Thus, any such methods using the inbred maize line 413A or aninbred maize plant of 413A further comprising one or more single genetraits are part of this invention: selfing, backcrosses, hybridproduction, crosses to populations, and the like. All plants producedusing inbred maize line 413A or inbred maize plants of 413A furthercomprising one or more single gene traits as a parent are within thescope of this invention. Advantageously, inbred maize line 413A orinbred maize plants of 413A further comprising one or more single genetraits are used in crosses with other, different, maize inbreds toproduce first generation (F1) maize hybrid seeds and plants withsuperior characteristics.

[0049] In a preferred embodiment, seeds of inbred maize line 413A orseeds of inbred maize plants of 413A further comprising one or moresingle gene traits are provided as an essentially homogeneous populationof inbred corn seeds. Essentially homogeneous populations of inbred seedare those that consist essentially of the particular inbred seed, andare generally purified free from substantial numbers of other seed, sothat the inbred seed forms between about 90% and about 100% of the totalseed, and preferably, between about 95% and about 100% of the totalseed. Most preferably, an essentially homogeneous population of inbredcorn seed will contain between about 98.5%, 99%, 99.5% and about 100% ofinbred seed, as measured by seed grow outs. The population of inbredcorn seeds of the invention is further particularly defined as beingessentially free from hybrid seed. The inbred seed population may beseparately grown to provide an essentially homogeneous population ofplants of inbred maize line 413A or inbred maize plants of 413A furthercomprising one or more single gene traits.

[0050] As used herein, the term “plant” includes plant cells, plantprotoplasts, plant cell tissue cultures from which maize plants can beregenerated, plant calli, plant clumps, and plant cells that are intactin plants or parts of plants, such as embryos, pollen, ovules, flowers,kernels, ears, cobs, leaves, husks, stalks, roots, root tips, anthers,silk, seeds and the like.

[0051] Duncan, Williams, Zehr, and Widholm, Planta (1985) 165:322-332reflects that 97% of the plants cultured that produced callus werecapable of plant regeneration. Subsequent experiments with both inbredsand hybrids produced 91% regenerable callus that produced plants. In afurther study in 1988, Songstad, Duncan & Widholm in Plant Cell Reports(1988), 7:262-265 reports several media additions that enhanceregenerability of callus of two inbred lines. Other published reportsalso indicated that “nontraditional” tissues are capable of producingsomatic embryogenesis and plant regeneration. K. P. Rao, et al., MaizeGenetics Cooperation Newsletter, 60:64-65 (1986), refers to somaticembryogenesis from glume callus cultures and B. V. Conger, et al., PlantCell Reports, 6:345-347 (1987) indicates somatic embryogenesis from thetissue cultures of maize leaf segments. Thus, it is clear from theliterature that the state of the art is such that these methods ofobtaining plants are, and were, “conventional” in the sense that theyare routinely used and have a very high rate of success.

[0052] Tissue culture procedures of maize are described in Green andRhodes, “Plant Regeneration in Tissue Culture of Maize,” Maize forBiological Research (Plant Molecular Biology Association,Charlottesville, Va. 1982, at 367-372) and in Duncan, et al., “TheProduction of Callus Capable of Plant Regeneration from Immature Embryosof Numerous Zea mays Genotypes,” 165 Planta 322-332 (1985). Thus,another aspect of this invention is to provide cells that upon growthand differentiation produce maize plants having the physiological andmorphological characteristics of inbred maize line 413A. In a preferredembodiment, cells of inbred maize line 413A are transformed genetically,for example with one or more genes described above, for example by usinga transformation method described in U.S Pat. No. 6,114,608, andtransgenic plants of inbred maize line 413A are obtained and used forthe production of hybrid maize plants.

[0053] Maize is used as human food, livestock feed, and as raw materialin industry. Sweet corn kernels having a relative moisture ofapproximately 72% are consumed by humans and may be processed by canningor freezing. The food uses of maize, in addition to human consumption ofmaize kernels, include both products of dry- and wet-milling industries.The principal products of maize dry milling are grits, meal and flour.The maize wet-milling industry can provide maize starch, maize syrups,and dextrose for food use. Maize oil is recovered from maize germ, whichis a by-product of both dry- and wet-milling industries.

[0054] Maize, including both grain and non-grain portions of the plant,is also used extensively as livestock feed, primarily for beef cattle,dairy cattle, hogs, and poultry. Industrial uses of maize includeproduction of ethanol, maize starch in the wet-milling industry andmaize flour in the dry-milling industry. The industrial applications ofmaize starch and flour are based on functional properties, such asviscosity, film formation, adhesive properties, and ability to suspendparticles. The maize starch and flour have application in the paper andtextile industries. Other industrial uses include applications inadhesives, building materials, foundry binders, laundry starches,explosives, oil-well muds, and other mining applications. Plant partsother than the grain of maize are also used in industry: for example,stalks and husks are made into paper and wallboard and cobs are used forfuel and to make charcoal.

[0055] The seed of inbred maize line 413A or of inbred maize line 413Afurther comprising one or more single gene traits, the plant producedfrom the inbred seed, the hybrid maize plant produced from the crossingof the inbred, hybrid seed, and various parts of the hybrid maize plantcan be utilized for human food, livestock feed, and as a raw material inindustry.

[0056] The present invention therefore also discloses an agriculturalproduct comprising a plant of the present invention or derived from aplant of the present invention. The present invention also discloses anindustrial product comprising a plant of the present invention orderived from a plant of the present invention. The present inventionfurther discloses methods of producing an agricultural or industrialproduct comprising planting seeds of the present invention, growingplant from such seeds, harvesting the plants and processing them toobtain an agricultural or industrial product.

DEPOSIT

[0057] Applicants have made a deposit of at least 2500 seeds of InbredMaize Line 413A with the American Type Culture Collection (ATCC),Manassas, Va., 20110-2209 U.S.A., ATCC Deposit No: PTA-4601. Thisdeposit of the Inbred Maize Line 413A will be maintained in the ATCCdepository, which is a public depository, for a period of 30 years, or 5years after the most recent request, or for the effective life of thepatent, whichever is longer, and will be replaced if it becomesnonviable during that period. Additionally, Applicants have satisfiedall the requirements of 37 C.F.R. §§1.801-1.809, including providing anindication of the viability of the sample. Applicants impose norestrictions on the availability of the deposited material from theATCC; however, Applicants have no authority to waive any restrictionsimposed by law on the transfer of biological material or itstransportation in commerce. Applicants do not waive any infringement ofits rights granted under this patent or under the Plant VarietyProtection Act (7 USC 2321 et seq.).

[0058] The foregoing invention has been described in detail by way ofillustration and example for purposes of clarity and understanding.However, it will be obvious that certain changes and modifications suchas single gene modifications and mutations, somaclonal variants, variantindividuals selected from large populations of the plants of is theinstant inbred and the like may be practiced within the scope of theinvention, as limited only by the scope of the appended claims.

What is claimed is: 1) Seed of maize inbred line 413A having beendeposited under ATCC Accession No: PTA-4601. 2) A maize plant, or partsthereof, of inbred line 413A, seed of said line having been depositedunder ATCC Accession No: PTA-4601. 3) Pollen of the plant of claim
 2. 4)An ovule of the plant of claim
 2. 5) A maize plant, or parts thereof,having all the physiological and morphological characteristics of aplant according to claim
 2. 6) The maize plant, or parts thereof, ofclaim 5, wherein the plant or parts thereof have been transformed sothat its genetic material contains a transgene operably linked to one ormore regulatory elements. 7) A method for producing a maize plant thatcontains in its genetic material a transgene, comprising crossing themaize plant of claims 2 or 6 with either a second plant of another maizeline, or a non-transformed maize plant of the line 413A, so that thegenetic material of the progeny that result from the cross contains thetransgene operably linked to a regulatory element. 8) A maize plant, orparts thereof, according to claim 2, further comprising a transgene. 9)A maize plant according to claim 8, comprising a transgene conferringupon said maize plant tolerance to a herbicide. 10) A maize plantaccording to claim 9, wherein said herbicide is glyphosate,gluphosinate, a sulfonylurea or an imidazolinone herbicide, ahydroxyphenylpyruvate dioxygenase inhibitor or a protoporphyrinogenoxidase inhibitor. 11) A maize plant according to claim 8, comprising atransgene conferring upon said maize plant insect resistance, diseaseresistance or virus resistance. 12) A maize plant according to claim 11,wherein said transgene conferring upon said maize plant insectresistance is a Bacillus thuringiensis Cry1Ab gene. 13) A maize plantaccording to claim 12, further comprising a bar transgene. 14) A maizeplant according to claim 12, wherein said CrylAb gene is introgressedinto said maize plant from a maize line comprising a Bt-11 event or a176 event. 15) Seed of a plant according to claim
 8. 16) A tissueculture of regenerable cells of a maize plant according to claim 2,wherein the tissue regenerates plants capable of expressing all themorphological and physiological characteristics of plants according toclaim
 2. 17) A tissue culture according to claim 16, the regenerablecells being selected from embryos, meristems, pollen, leaves, anthers,roots, root tips, silk, flowers, kernels, ears, cobs, husks and stalks,or being protoplasts or callus derived therefrom. 18) A maize plantregenerated from the tissue culture of claim
 17. 19) A method fordeveloping a maize plant in a maize plant breeding program using plantbreeding techniques, which include employing a maize plant, or itsparts, as a source of plant breeding material, comprising: obtaining themaize plant, or its parts, of claim 2 as a source of said breedingmaterial. 20) A maize plant breeding program of claim 19, wherein plantbreeding techniques are selected from the group consisting of: recurrentselection, backcrossing, pedigree breeding, restriction fragment lengthpolymorphism enhanced selection, genetic marker enhanced selection, andtransformation. 21) A maize plant, or parts thereof, produced by themethod of claim
 19. 22) A method for producing maize seed comprisingcrossing a first parent maize plant with a second parent maize plant andharvesting the resultant first generation maize seed, wherein said firstor second parent maize plant is the inbred maize plant of claim
 2. 23) Amethod according to claim 22, wherein inbred maize plant of claim 2 isthe female parent. 24) A method according to claim 22, wherein inbredmaize plant of claim 2 is the male parent. 25) An F1 hybrid seedproduced by the method of claim
 22. 26) An F1 hybrid plant, or partsthereof, grown from the seed of claim
 25. 27) A method comprising: a)planting a collection of seed comprising of a hybrid, one of whoseparents is a plant according to claim 2, or a maize plant having all thephysiological and morphological characteristics of a plant according toclaim 2, said collection also comprising seed of said inbred line; b)growing plant from said collection of seed; c) identifying said inbredplants; d) selecting said inbred plants; and e) controlling pollinationin a manner which preserves the homozygosity of said inbred plant.